I think you'll have to register your Kindle to your account. I see in another thread you don't have wifi, so you will need to log into your Amazon account from your PC, goto "Manage your Kindle" and hit Register. You'll need the serial code of your Kindle.

From there you should be able to buy Amazon ebooks, download them from your account and copy to your Kindle via USB.

Solicitous is completely correct. You just have to register your Kindle to your Amazon account. To do that, you need to know your Kindle's serial number (not the same as its PID). The serial number is printed on the back of the device.

Alex, if you mean reading DRMed Kindle books from Amazon, then the posts above are correct, certainly, but I'd think that would be pretty obvious (and the Kindle itself pretty much walks you through that depending on the condition it was in when you got it).
Were you perhaps asking about reading DRMed mobis from sources OTHER than Amazon?

The device PID for Kindles that have software versions greater than or equal to 2.5 would only be needed in some very, very specific circumstances. As others have said, it's not necessary at all for Amazon purchases... and you probably still don't have to worry about it even if you start "branching out" and using other ebook sellers.

Alex, if you mean reading DRMed Kindle books from Amazon, then the posts above are correct, certainly, but I'd think that would be pretty obvious (and the Kindle itself pretty much walks you through that depending on the condition it was in when you got it).
Were you perhaps asking about reading DRMed mobis from sources OTHER than Amazon?

ApK

Yes, I bought several books from Fictionwise, and want to download them again for use on the Kindle - especially the updated LOTR. I should have been more clear in my own mind before posting, and then the post would made more sense.

Solicitous is completely correct. You just have to register your Kindle to your Amazon account. To do that, you need to know your Kindle's serial number (not the same as its PID). The serial number is printed on the back of the device.

Thanks, Solicitous and Mike. I bought the Kindle through my Amazon account, and according to the manual this should have registered it automatically. But it didn't, so I'll follow your advice.

Yes, I bought several books from Fictionwise, and want to download them again for use on the Kindle - especially the updated LOTR. I should have been more clear in my own mind before posting, and then the post would made more sense.

If it and your other purchases from Fictionwise are DRM'ed, your only real choice is to remove the DRM before loading it onto your Kindle. The only DRM the Kindle will recognize/use/allow is Amazon's own.

We used to be able to give Fictionwise our Kindle's device PID to download an encrypted mobi, but even then, you still had to "tweak" the DRM to get it to actually work on the Kindle. I don't think that even works anymore--but I could be wrong.

The most recent copies of the kindlepid script that are floating around will generate a device PID for the Kindle 3, but that PID just won't do you any good any more (except in rare circumstances).

DD can correct me if I'm wrong, but you could still use the device PID if you wanted to CONTINUE buying DRMed mobis or borrowing library mobis.
You would add the PID to your account on the book site, and also configure the appropriate deDRMing tool with the same PID. I guess ANY PID would work in that scenario, even a made up one or the one from your previous device, but using your real one lends credibility....

I have tried it with the National Library Singapore, (http://singapore.lib.overdrive.com) entered the above generated Kindle PID and the book downloaded was readable on the kindle as protected content!

I have tried it with the National Library Singapore, (http://singapore.lib.overdrive.com) entered the above generated Kindle PID and the book downloaded was readable on the kindle as protected content!

Did you put the downloaded file into Calibre (or do anything else with it) first, or did you download it to your PC and put it DIRECTLY on your Kindle?

I could have sworn doing directly had worked for me in the recent past, even after the breaking change from Amazon a few months ago, but in subsequent tests I could not get it to worked unless I put it through Calibre (with some third party plugins) first.

If you did it directly, please tell me what title it was so I can try it too.

DD can correct me if I'm wrong, but you could still use the device PID if you wanted to CONTINUE buying DRMed mobis or borrowing library mobis.

This is correct.

But I don't think the PID ever worked (right out of the box, anyway) with Fictionwise's DRM scheme... hence why the kindlefix python script originally became necessary to "fix" the DRM, so the protected content could be read on the Kindle.

A long time ago, you could use the Kindle PID with Fictionwise Secure Mobi, but they changed DRM servers long ago, and you can't even enter some of the characters that are required for a Kindle PID any more.

I have tried it with the National Library Singapore, (http://singapore.lib.overdrive.com) entered the above generated Kindle PID and the book downloaded was readable on the kindle as protected content!

Thanks, Calvin, but the site says it only works for Kindle2, and I have a Kindle3. I tried anyway, but didn't get a legible response.